This is a competitive renewal application for continued support of a postdoctoral research career development program for obstetrician-gynecologists in fundamental research in reproductive medicine and biology. It is sponsored jointly by the NIH/NICHD, six professional organizations, three pharmaceutical corporations, and three research foundations. The objective of this program is to educate obstetrician-gynecologists in contemporary basic science research to prepare them for research careers in academic medicine. The goal is to help ensure that academic obstetrics and gynecology fulfills its mission to increase research and discovery in the reproductive sciences. Outstanding Ph.D. and M.D. scientists with broad research experience serve as faculty. A unique feature of this program is that outstanding individuals, upon completion of residency, and in many cases two or three years of clinical subspecialty fellowship, spend two to three years in fundamental research laboratories under the supervision and mentorship of experienced, well-screened, and accomplished scientists (Phase I). Following this experience, scholars spend an additional three-year period establishing their research programs in a Department of Obstetrics and Gynecology (Phase II). During Phase I, scholars are dedicated to full-time research. Following this basic research, the scholar spends three years as a junior faculty member in a Department of Obstetrics and Gynecology with at least 75% time free to develop an independent research career. Phase II is funded from a number of possible sources, including NIH and private grants, and several from contributions to the [Reproductive Scientist Development Program] RSDP program from the profession, from philanthropic foundations, industry, and personal sources. Upon completion of this program, the candidate is expected to continue to pursue a career as a productive investigator. This program serves as a model to educate increased numbers of reproductive scientists to develop into leaders in academic Departments of Obstetrics and Gynecology. The RSDP's plan for career development serves as a model for postgraduate medical education, and assures that some of the most promising young physician-investigators in the country will remain in academic investigative obstetrics and gynecology. A great majority of the scholars who have finished Phase II of the Program have dedicated themselves to research in the reproductive sciences and have developed major independent funding support. To date, their productivity has been outstanding, and is a credit to the Program.